Expansion reamer



March 8, l92'7.,.4 1,619,855

E. E. DAVIS EXPANSION BEAMER filed oct. 27, 1522 Patented Mar. 8, 1927.

Ultll'l JL;

tasses. raser errer..

EMERY E. DAVIS, F ST. LO'US, MSSGUB/, ASSGNOR T0 DAVS BOB/ENG- TOOL COM- PANY, 0F ST. LOUS, MISSQURI, A CRPORATON OF MSSGUR.

EXPANSON BEAMER.

Application filed ctober 2.7, 1922. Serial No. 597,302'.

eration should not disturb that location. As

the reamer is usually mounted rigidly in a support, it is necessary to aline the reainer very accu at-ely so that it shall out a uniformv amount from all sides ol the hole and leave the centering undisturbed. It the reainer is not accurately alined, it will cut a greater amount from one side than from the other and thus the position oli the center ot the hole will be displaced.

@ne ot the objects ot this in ventloi'utherefore, is lo provide a reamer which will have a. certain amount ot play so that it may adjust itself to the alinement ot the hole to be reamed.

Another object ot this invention is to provide a rcamer with a Heating head which will adjust itsell1 to the position olE the hole.

Further objects will appear from the detail description taken in connection with the accompanying drawing, in which:

Figure 1 represents a sectional view of an expansion type reaiuer embodying this invention;

Figure 2 is an end view of Figure 1; and

Figure 3 is a detail section on line 3-3, Figure 1.

Referring to the accompanying drawing, 1 designates the shank of a rea-mer by means ot which it is mounted in the machine or holder in which it is to be used. The shank is provided with a flange 2 and a cylindrical extension 3. The extension 3 is adapted to extend into the head e of the reamer. Clearance is allowed between the extension 3 and the bore of the head into which it lits so as to permit a certain limited amount of play between the two. A few thousandths of an inch is ordinarily enough. The extension 3 thus :torms a bearing extending loosely into the head and serving to guide and support the same, while at the same time, allowing a certain amount of free movement radially and axially. Near the extremity of the extension 3 a portion 5 thereof is formed with an angular outline, a square outline being shown, which fits loosely into a corresponding socket 6 in the head e. This connection allows sufficient clearance so as not to restrict the free movement above nie* tioned.

The end of the shank may be reduced and provided with a thread 7 adapted to engage a nut S or other suitable fastening device so as to maintain the head in place on the shank. rlhe nut 8 is shown provided with depressions 9 which may be engaged by a suitable wrench for screwing up the nut. The angular part and its socket 6, therefore, provide a loose coupling or driving connection by means of which the head '4.- may be driven during the cutting operation..

The head 4 may be provided with a series ol slots l() adapted to form seats for a series ot blades or cutters ll. 'lhe bottoms 12 ot the slots 10 may be arranged to incline outwardly toward the tip of the head and the bottom edges of the blades 1l may be correspondingly tapered so that upon .movement ot the blades 11, along the Vslots and toward the tip, said bladesl will be expansiblc. An adjusting ring 13 screw threaded on the head may be arranged to engage the rear faces ot the blades l1 so as to adjust the position ot the same along the slots 10. Such adjustment will also adjust the external diameter of the cutters. A backing ring 111 may be arranged to engage the rear ot the ring 13 to secure the same in adjustment. rlhe cutters may be provided with grooves lmatching with grooves 16 in the head 4t into which pins 17 may be driven so as to secure the blades 11 in their seats.

The flange 2 may be provided with a shoulder 18 adapted to match a corresponding shoulder on the head 4 forming a rib and channel connection so as to provide a dust shield to prevent dust and dirt entering between the shank extension 3 and the head 4. The flange 2, moreover, provides a backing for the head to protect the rear thereof and to assist in taking the thrust.

In order to permit adjustment of the rings 13 and 14, these are not provided with the usual sockets, but they are recessed as shown at 2() in order to provide bottom faces on opposite sides ot the rings which are parallel in order to receive a wrench. These taces. do not, however, extend the entire width of a ring, but walls 21 are left on both sides oi' a recess so that the strength of the ring will be maintained.

It will be noted that this invention provides a simple and useful tool tor realising,l and one which will aline itself in the hole. The loose tit between the bearing` 3 and the head 4 provides tor tree movement ot' the head radially and axially so that during the cutting operation, the head tloats on the shank and by means ot' the loose driving` connection provided by the angular nieniber 5, the cutters are driven lor roaming. rlhe diameter ot the cutters is adjustable and lthe entire device is so constructed that parts are easily renewable when worn.

n 1t is obvious that various changes may be made in details without departing iroin the spirit ot this invention; it is, therefore, to be understood that this invention is not to be limited to the speoitic detailsshown and described.

Having thus described the invention, what is claimed is:

l. A reamer Comprising, a shank, a head loosely mounted on said shank and provided with cutting edges, aV loose angular driving;v connection between said head an d said shank at the tip of said head, and an overliangg'ingf;l shoulder on one part loosely entering a recess in the other part at the back otI said head adapted to provide a dust seal.

2. A reamer comprising, a shank, a head loosely mounted on said shank and provided with cutting edges, a reduced angular part on said shank loosely engaging a corresponding opening at the tip ot said head,

and an overhanging shoulder on one part loosely entering a recess in the other part at the back ot said head adapted to provide a dust seal. Y

3. A reamer comprising, a shank, a head loosely mounted on said shank and provided with cutting edges, a reduced angular part on said shank loosely enga, 'in a corresponding opening at the tip of said head, a nut on the end otl said shank loosely entering a recess on said head, and an overhanging shoulder on one part loosely entering' a recess in the other part at the haci ot said head adapted to provide a dust seal.

4. A. reamer comprising, a shouldered shank, a head loosely mounted on said shank f andV provided with cutting edges7 an angular driving' connection between said head and the tip ot said shank, a groove in the shouldered part of said shank7 and a projection on the rearward part of said head adapted to en- `rage said groove to provide a dust seal. said projection also serving' to back up said head.

5. A reainer comprising, a shank. a head loosely mounted thereon andV provided with cutting edges, an angular driving connection between said shank and the tip ot' said head, and a flange on said shank adapted to provide a barking, and having' a rib and channel connection with said head.

In testimony whereof I aiiix my si gnature this 'lst day ot Sept., 1922.

EMERY E. DAVIS. 

